Best Telephony & PBX tools by public signals

These picks are computed from scored public evidence. Use the openness column in the ranking to separate OSI-approved, source-available, open-core, proprietary, and unverified-license tools.

Use Case Rankings

Ordered by ToolVitals score, then health, shipping, confidence, GitHub stars, and name.

#ToolHealthShippingOpennessStarsScoreStatus
01Kamailio
Kamailio - The Open Source SIP Server for large VoIP and real-time communication platforms, focusing on flexibility, security and scalability
9796OSI-approved OSS2.9k97Active
02dograh
Open-source voice agent platform.
9796OSI-approved OSS5.6k96Active
03FS PBX
Open-source PBX platform for business telephony and VoIP deployments.
9695OSI-approved OSS23095Active
04MikoPBX
Open-source PBX for small business built on Asterisk.
9293OSI-approved OSS57293Active
05Linphone
Linphone is a free VoIP and video softphone based on the SIP protocol. Mirror of git://git.linphone.org/linphone-desktop.git
8781OSI-approved OSS50385Active
06Fonoster
🚀 The open-source alternative to Twilio.
8483OSI-approved OSS8.1k84Active
07ICTFAX
Open source fax server software for inbound and outbound faxing with API integration.
6756OSI-approved OSS23662Warning

Not Scored

Tracked for context, but excluded from rankings because comparable open/source-visible evidence is unavailable.